Effectiveness of tenapanor for treating hyperphosphatemia in patients receiving dialysis: a plain language summary of the OPTIMIZE study

Plain Language SummaryWhat is this summary about?This summary provides a review of the OPTIMIZE study, the results of which were published in Kidney360 in February 2024. The OPTIMIZE study looked at how well tenapanor tablets work to treat patients receiving dialysis who have high levels of phosphate in their blood, a condition called hyperphosphatemia. In the OPTIMIZE study, researchers wanted to understand if tenapanor would decrease phosphate levels in the blood to the target range. They also tested different ways of starting tenapanor treatment in patients.In the human body, kidneys are organs that filter blood and remove waste products. In chronic kidney disease, sometimes referred to as CKD, a patient's kidneys do not work as well at filtering their blood and removing waste products. This can allow phosphate to build up in the blood. Phosphate levels may remain high despite patients receiving treatment such as dialysis, using pills that keep phosphate in the intestines (called phosphate binders) to prevent phosphate from being absorbed into the blood, and eating a low-phosphate diet. Phosphate levels may remain high despite these treatments because they can be difficult to follow. Most people receiving dialysis take 7–8 phosphate binder pills every day, and over half of those people have reported skipping at least one dose in the past month. Additionally, low-phosphate diets can be difficult to follow and people often struggle to meet their other nutritional needs.What are the key takeaways?Tenapanor used in combination with phosphate binders led to lower phosphate levels in the blood with the use of fewer phosphate-lowering pills. Tenapanor also lowered phosphate levels in patients who were not previously on phosphate binders but needed phosphate-lowering treatment.What were the main conclusions reported by the researchers?Tenapanor can help patients receiving dialysis better control their hyperphosphatemia.This is an abstract of the Plain Language Summary of Publication article.View the full Plain Language Summary PDF of this article to read the full-textLink to original article here Declaration of financial/other relationshipsSMS receives research grants from and is a consultant for Ardelyx, Inc. SE, DMS, and DPR are employees of Ardelyx, Inc. CT declares no conflict of interest.DEW is the Medical Director of Clinical Research for Dialysis Clinic, Inc. (DCI) with institutional support from DCI paid to Tufts Medical Center. Dr. Weiner was a site Principal Investigator for several tenapanor clinical trials from Ardelyx, Inc. (not compensated). The authors have no other competing interests or relevant affiliations with any organization or entity with the subject matter or materials discussed in the manuscript apart from those disclosed.Reviewer disclosuresPeer reviewers on this manuscript have no relevant financial or other relationships to disclose.AcknowledgementsWe would like to thank the patients and investigators who participated in the study. The OPTIMIZE study has previously been presented at the 58th European Renal Association–European Dialysis Transplantation Association (ERA-EDTA) Congress 2021 and the National Kidney Foundation (NKF) Spring Clinical Meeting 2022. One patient author coauthored this summary and added her perspective.Writing disclosureMedical writing support was provided by Katherine Cashell, from Ashfield MedComms (New York, NY, USA), an Inizio company, and was funded by Ardelyx, Inc. (Waltham, MA, USA).Company review disclosureIn addition to the peer-review process, with the authors' consent, the manufacturer of the product discussed in this article was given the opportunity to review the manuscript for factual accuracy. Changes were made by the authors at their discretion and based on scientific or editorial merit only. The authors maintained full control over the manuscript, including content, wording and conclusions.Data availabilityArdelyx will consider reasonable requests for data sharing such as the study protocol, SAP, and ICF on a case-by-case basis based on data availability, burden, and data privacy issues. This will go into effect immediately after publication for a period of up to 1 year. Data will be shared to achieve aims in an investigator-submitted proposal, which has been approved by Ardelyx. Proposals should be directed to medinfo@ardelyx.com. To gain access to data, requestors will need to sign a data access agreement.Ethics approval and consent to participateAll patients provided written and informed consent before study entry. Study site investigators ensured the study protocol was approved by the appropriate institutional review board and/or independent ethics committee prior to trial initiation. The trial was conducted in accordance with the Declaration of Helsinki, Good Clinical Practice Guidelines, and all applicable local laws and regulations.Open accessCC-BY-NC-ND: This work is licensed under the Attribution-NonCommercial-NoDerivatives 4.0 Unported License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-nd/4.0/Copyright holder: The authors (Stuart M. Sprague, Daniel E. Weiner, David P. Tietjen, Pablo Pergola, Steven Fishbane, Geoffrey A. Block, Arnold L. Silva, Stephen Z. Fadem, Robert I. Lynn; George Fadda, Lynae Pagliaro, Suling Zhao, Susan Edelstein, David M. Spiegel, and David P. Rosenbaum).Additional informationFundingThis study was funded by Ardelyx, Inc., 400 Fifth Avenue, Suite 210, Waltham, MA 02451. Tel: 617.675.ARDX (2739). Email: info@ardelyx.com. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from this disclosure.